Central venous catheters , types

Moretti EW, Ofstead CL, Kristy RM, et al. Impact of central venous catheter type and methods on catheter-related colonization and bacteraemia. J Hosp Infect October 2005 61(2) 139 5. 

Osmolarity of the nutrient admixtures and thereby the infusion route is determined by the type and amount of the components mixed. In general the admixtures are hyperosmolar and to be administered via a central venous catheter in a big vein (vena cava superior or vena subclavia). Only admixtures with a maximum osmolarity of900 mOsm/ L can be administered via a peripheral vein and only for a limited period of time [69]. Lmig term parenteral nutrition can be also administered via a port (see Sect. 13.10.3) especially when patients are treated at home. Because of the high probability of incompatibilities nutrition admixtures should always be administered via a separate line and Y-site infusion should be avoided. 

MidUne catheters and peripherally inserted central catheters (PlCC) are inserted in a peripheral vein but the tip rests in a larger vein. The infusion fluid flows directly in the larger vein which diminishes the chance of phlebitis. Both types of catheters are typically inserted in a vein in the upper arm. The midline catheter ends at armpit height the tip of the PICC rests in the vena cava superior. The PlCC may have single or multiple lumens. The PlCC line can be used as a central venous catheter for infusion which needs fast dilution or distribution or both such as antibiotics, pain medicine, chemotherapy, nutrition, etc. 

Many different types of venous-access devices are available. Peripherally inserted central venous catheters (PICCs), which can be made of PU or silicone, are inserted into a vein in the arm rather than in the neck or chest. Nontunneled CVCs are shortterm catheters, made of PU or silicone as well, inserted into the internal jugular, subclavian, or femoral vein. Tunneled CVCs are long-term catheters implanted surgically under the skin. One end of the catheter remains outside the skin and the exit site is typically located in the chest. Passing the catheter under the skin helps to reduce the infection risk and provides stability. Implantable ports are similar to tunneled catheters but are left completely under the skin. They consist in small devices, made of plastic or titanium, inserted beneath the skin and connected to a catheter allowing vascular access. Under the skin, the port has a septum through which drugs can be injected and blood samples can be withdrawn. 

Walder B, Pittet D, Tramer MR. Prevention of bloodstream infections with central venous catheters treated with anti-infective agents depends on catheter type and insertion time evidence from a meta-analysis. Infect Control Hosp Epidemiol December 2002 23(12) 748-56. 

Stoiser B, Kofler J, Staudinger T, et al. Contamination of central venous catheters in immunocompromised patients a comparison between two different types of central venous catheters. J Hosp Infect March 2002 50(3) 202-6. 

Medical and nursing staff dealing with central venous catheters (CVC) should be aware of specific risk factors and safety hazards associated with this access type (damage of the vessels and/or surrounding tissue at CVC insertion, fibrin sheath formation, leak of the anticoagulation lock solution into the vascular system, etc.). 

Central venous catheters (CVC) are generally considered an inevitable evil [1]. Their use is ever growing (see for instance DOPPS data from Germany an increase from 5.3% in 2002 to 19.4% in 2010 despite all recommendations to limit it [2]). Many studies have demonstrated higher morbidity and mortality associated with CVC compared to permanent subcutaneous access types [3] and the effort to limit their use is thus fully understandable. On the other hand, CVC does not affect patient hemodynamics and bears no risk of hyperkinetic circulation. 

Hemodialysis (HD) catheter-associated bloodstream infections (BSls) are a type of CLABSI due to a central venous catheter (CVC) specifically designed for HD. In 2002, it was estimated that 50,000 CLABSIs occur in dialysis patients in the US annually. A more recent surveillance study found the rate of access-related BSIs to be 0.73 events per 100 patient-months [5]. Aside from catheters, patients in need of renal replacement therapy should eventually use arteriovenous fistula (AVF) or arteriovenous grafts (AVG) for HD, or alternatively, may receive peritoneal dialysis. All renal replacement therapies are associated with a risk of infection however, this risk varies with the method selected. Data from a CDC surveillance program display nicely how the type of access influences the BSI rate per 100 patient-months 0.5 (for AVFs), 0.9 (AVG), 4.2 (permanent CVCs), and an impressive 27.1 for temporary CVCs [6]. Another, more practi-... 

Biomaterials are materials foreign to the human body that are used in medicine to replace, support or restore body function. Applications range from central venous and urinary catheters to more complex devices such as prosthetic joints and heart valves. The risk of biomaterial centered infection (BCI) is a key factor limiting their use [1]. The incidence of this type of infections varies for each application for instance 4% for hip prostheses [2] and 10-20% for urinary catheters (see Table 1). In BCI microorganisms are present in close association with the biomaterial surface forming a so-called biofilm. Different species of microorganisms are found in BCI that are often commen-... 

There is some disagreement as to whether infectious complications differ with the use of different types of chronic central venous access devices in patients with cancer. In one study there was no significant difference in the risk of infection between subcutaneous ports and external catheters (26). However, this has been disputed by other workers, who found that in children with cancer there was a lower infection rate when subcutaneous ports were used compared with external catheters (27). The differences between the studies and the conclusions reached may be the result of their size and design, rather than real differences. 

The incidence and duration of phlebitis seems to be dependent on a variety of factors. Physical-chemical factors such as low pH, hypertonicity, particles and precipitation play a role in the cause. Active substances that are poorly soluble in water may precipitate and can cause acute phlebitis. Active substances with adequate aqueous solubility may tend to cause phlebitis only because of prolonged or chronic administration. Clinical factors involving injection technique (infiltration, extravasation, type of needle, duration of infusion) but also irritating characteristics of the active substance can contribute to the occurrence of phlebitis [9, 10]. Sometimes (septic) phlebitis is caused by bacterial infection (e.g. cause of inappropriate aseptic technique during catheter insertion) and is characterised by inflammation with suppuration of the vein wall. Local responses to the parenteral challenges can be diminished by dilution of the medicine or by central venous instead of peripheral venous administration (see Sect. 13.10.3). 

The incidence of Candidiasis reported in this series is disturbing because of the recent association of Candidiasis with parenteral nutrition, by Ashcraft and Leape (5). The work of MacMillan, Law and Holder, however, documents the increasing problem of Candida in the burned child (6). Because of the number of variables involved, it is difficult in this series to assess the relationship between Candidiasis and central venous nutritional supplementation. The clinician caring for this type of patient, however, should be aware of this etiologic possibility when sepsis presents and treat when present by removing catheters and giving Amphotericin B. 

Stenosis is a common problem for AVFs and AVGs and represents the main cause of dysfunction and thrombosis, and the choice of the best method for repair depends on the location of the lesion. Access stenosis has been classified based on its location as juxta-anastomotic (type I), in the cannulable segment (type II) and at the outflow into the deep venous system (type III) [4] (fig. 1). There are two additional categories of stenoses not involving the access itself, those of the central veins caused by longstanding catheters and those of the arterial inflow [5]. 

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